Refrigerating apparatus



Sept 9, 1958 l.. A. PHlLlPP 2,850,883

REFRIGERATING APPARATUS Filed April 21, 1955 2 Sheets-Sheet 1 Sept. 9,1958 L. A. PHILIPP 2,850,883 f REFRIGERATING APPARATUS Filed April 21,1955 2 sheets-sheet 2 I'J. l "'z Y 359;??? f- 66 'II'INIIIIII'I'IIIIIILINVENTOR. dh/E//K' Fla /PP 1T l n ,mbsf i states @tt REFRIGERATENGAPPARATUS Lawrence A. Philipp, Detroit, Mich., assigner to AmericanMotors Corporation, Detroit, Mich., a corporation of MarylandApplication Apri-1121, 1s ss, serai No. 502,791

1 cnam. (crm- 1an The present invention pertains to refrigeratingapparatus and more particularly to a cooling of the compressor andcondenser used in such apparatus.

One of the objects of my invention is to provide an improved arrangementfor dissipating the heat of condensation from a refrigerant condensingelement.

Another object of my invention is to provide an improved arrangement forcontrolling the flow of air over a refrigerant motor-compressor unit andrefrigerant condenser assembly.

It is another object of the present invention to provide a condenserhaving suciently large surface area to provide for the effective coolingand condensing of the refrigerant vapors by the natural flow of air`thereover and being so arranged that only a portion of the cooling airwill ow therefrom to provide cooling of a motor compressor unit.

It isanother object of the present invention to provide a condenserarranged in two sections havinga combined surface cooling area foreffective cooling and condensing refrigerant vapor by natural ow of airthereacross and when the ambient temperature attains a predeterminedhigh value to provide a forced circulation of cooling air over onesection of the condenser to effect full cooling and .condensing of therefrigerant therein requiring little or no cooling as the refrigerantyis conducted through the other section of the condenser.

It is another object of the present invention to provide a motoroperated fan for forced circulation of airV across a motor-compressorunit and a portion of a condenser whereby the fan is thermostaticallycontrolled to operate only when the ambient temperature attains apredetermined high value.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein a preferred form of the present invention is clearlyshown.

ln the drawings:

Fig. 1 is a front view of a refrigerator embodying features of myinvention and showing a portion thereof broken away;

Fig. 2 is a side View of the refrigerator showing a portion thereofbroken away;

Fig. 3 is a view in cross section taken along line 3-3 of Fig. l

Fig. 4 is a view in cross section taken along line 4-4 of Fig. l;

Fig. 5 is a diagrammatic illustration of the refrigeration systemembodying features of my invention; and

Fig. 6 is a diagrammatic illustration of the controls in a wiringdiagram embodying features of my invention.

Referring to the drawing, the numeral 20 designates in general arefrigerator cabinet having a food storage compartment 22 and a machinecompartment 24. The food storage compartment 22 is adapted for thestorage of frozen foods, ice cream and the like, and is formed within aninner sheet metal liner 26 supported in :spaced relation Qto an outersheet metal casing or wrapper 2S of the cabinet 20. VInsulation 29 isinterposed between the liner 26 and the casing 28. The food storagecompartment has an opening at the topthrough which access-to theinterior of the compartment may be had, and which opening is closed .bysuitable lids or closure members 30.

The cabinet 20 rests upon and is secured to a supporting frame 32 whichcomprises rails 34, 36 and 37. The rails 34 and 36 extend parallelto afront wall 38 and rear Wall 40 of the outer sheet metal .casing 28 ofthe cabinet. The rail 37 extends parallel to end wall 42 of the casing28 to join one end of rails 34 and 36 whose opposite ends are notconnected to provide access opening 44 to a space or passageway 46formed within the frame 32 between the bottom of the cabinet and oor.The space or passageway 46 is in open communication with the machinecompartment 24 whose walls include end wall 42, front wall 38, rear wall40 of the outer casing 28 and a sheet metal partitional wall 50. Accessto the machine compartment 24 is provided by opening 52 formed in frontwall 38 of the casing. A guard grill or screen 54 is placed across theopening52.

To refrigerate the food storage compartment 22 there is provided arefrigerating system designated in general by the numeral 60, comprisinga hermetically sealed motorcompressor unit 62, a condenser 64 consistingof two sections 66 and 68, refrigerant evaporating coils 70 serpentinedabout and bonded in thermal heat exchange relation to the exteriorsurface of the inner sheet metal liner 26, and an accumulator 72.

The motor-compressor unit 62 is secured on frame 74 which rests uponsupporting guide rails 76. The frame is slideable on the rails 76 tofacilitate the placement of the unit 62 into the machine compartment, orfor its removal from the machine compartment. The rails 76 extendbetween the supporting frames rails 34 and 36 and are secured thereto.Also supported on the frame 74 by a bracket 78 is a motor 80 having ashaft` 82 upon which is secured a fan 84.

The .condenser plate section k66of the condenser-64 is adapted to bepositioned within thespace 46 land includes refrigerant conduit'90serpentined about and secured to a surface of a sheet metal lplate 92which plateprovides a iinned surface. The sheet metal .plate 92 issuspended and secured in spaced parallel relation tothe bottom wall ofthe cabinet `20.by brackets 96. The conduit may be thermally bonded tothe plate .92 by weld, straps, or by any vother well known means. Thecondenser section '68L is a continuation Vof the condenser section 66and includes refrigerant conduit 98 Vserpentined to extend about theinner surface ofthe'front and rear walls ofthe outer sheet metal .casing28. The conduit 9S is bonded in thermal heat exchange relation with thecasing 2S. Y Y

Tov control tand Vregulate Vthelfoperationfor the ymotorcompressor unit62 there is provided a thermostatic control which is responsive to thetemperature of the food storage compartment 22. A second thermostaticcontrol 112 is provided to control and regulate the operation of the fan84. The thermostatic control 112 includes a switch mechanism 114 and athermo-sensitive power element 116 positioned to be in close proximityto the shell of the motor-compressor unit 62. The switch mechanism andpower element of the thermostatic control 112 are supported within andprotected by a metallic shield 118 which is secured by leg 117 to theframe 74. The shield is formed with a front opening as at 120, and anopen bottom as at 122. The opening 12) is arranged so that thethermo-sensitive power element is exposed to the direct heat radiationfrom the shell of the unit 62. The air after cooling the condenser andflowing upwardly into the machine compartment may enter through bottomopening 122 to influence or effect a modification of the influence ofthe shells heat upon the ythermo-sensitive power element.

In operation to cool the food storage compartment 22,

the vaporized or heat laden refrigerant is withdrawn from the evaporatorinto the accumulator wherein theliquid refrigerant is separated from thevaporized, the vaporized or gaseous refrigerant is .conducted into themotor compressor unit 62 to be compressed by` the compressor anddischarged to flow through the condenser 64.- The refrigerant firstflows through the plate section 66 and then the section 68 of thecondenser to be cooled, condensed and then metered and conducted througha small diameter conduit to the evaporator coils 70.

Normally, during periods when the ambient temperature is preferablybelow 80 F., the condenser and motorcompressor unit may be effectivelycooled by natural flow of air passing thereover. Air enters throughopening 44 into the space 46 to flow over and around the condensersection 66 then passes upwardly into the machine compartment to cool themotor-compressor unit and passes through opening 52 outwardly to theatmosphere. Vaporous refrigerant in the section 68 of the condenser iscooled and condensed by the air circulating about the exterior of thecabinet. When the ambient temperature attains about 80 F. cooling bynatural convection is ineffective for eicient operation and as thetemperature of the refrigerant rises there is a corresponding rise intemperature in the motor-compressor unit to iniiuence and actuate thethermostatic control 112 to energize the motor 81) and operate the fan84 for the forced circulation of air which is drawn through opening 52into the machine compartment to cool the motor-compressor unit then passthrough space 46 to cool the condenser section 66 to pass outwardlythrough opening 44 to the atmosphere. An opening 130 is formed in thefront rail 34 to provide an additional access opening for circulation ofair about the condenser 66.

The thermostatic control 112 is arranged to be connected in series withthe thermostatic control 110 (see Fig. A6) so that the fans motor 80will be energized during periods that the motor-compressor is operating.However, the fans motor 80 will only be energized whenever the ambienttemperature rises so that cooling by natural convection is ineffectiveand forced circulation of air is essential.

The above arrangement is such that by forming a portion of the condenserto lie in the path of a channelled air stream and a portion of thecondenser bonded to the eX- terior Wall of the cabinet to utilize thewall to radiate heat therefrom, there is a compact arrangement forproviding a large surface area necessary when natural convection coolingis desired. Further this arrangement also permits the refrigerant to beconsecutively cooled by air of the same temperature that is the airpassing around the condenser section 66 does not serve to cool theexterior walls of the cabinet while the air cooling the exterior of thecabinet does not serve to cool the condenser section 66 and themotor-compressor unit. Also, as the air entering the space 44 onlyserves to cool the portion 66 of the condenser 64 it would not become soheated as to be in-` effective to cool the motor-compressor unit beforepassing to the atmosphere. However, when ambient temperature rises aboveF., the fan motor S0 is energized to operate the fan for passing airacross the compressor unit then the condenser 66. The condenser 66 is soarranged that when forced air circulation is provided it willeffectively cool and condense the compressed refrigerant therein so thatlittle or no further cooling is required of the refrigerant as it passesthrough the condenser section 68 thereby permitting the exterior wall ofthe cabinet to be held at atmospherical temperature and heat leakage tothe food compartment is held at a minimum.

Although only a preferred form of the invention has been illustrated,and that form described in detail, it will be apparent to those skilledin the art that various moditications may be made therein withoutdeparting from the spirit of the invention or from the scope of theappended claim.

I claim:

Refrigerating apparatus comprising a cabinet having a food storagecompartment and a second compartment having an open bottom and an openside, refrigerating means for said food storage compartment including anevaporator, a motor-compressor unit, a condenser connected to saidmotor-compressor unit, said condenser having a first section and asecond section connected in series relation, said first section beingarranged in horizontal position in the lower part of said secondcompartment, said second section being bonded in thermal heat exchangerelation to the outer wall of said cabinet and being isolated from saidmotor-compressor unit and the condenser first section, saidmotor-compressor unit being positioned in said second compartmentadjacent to and above said condenser first section so that heatdissipated from said condenser first section passes by naturalconvection over said motor-compressor unit and out the open side of saidsecond campartment, temperature responsive fan means for causing thecirculation of air through the open side of said second compartment andoversad motor-compressor unit and then over said first section of saidcondenser and out the bottom side of said second compartment, andthermostatic means for controlling the operation of said fan means, saidthermostatic means being arranged to be responsive to the environmenttemperature about said motor-compressor unit.

References Cited in the tile of this patent UNlTED STATES PATENTS Y1,769,119 Davenport July 1, 1930 2,135,091 Newill Nov. 1, 1938 2,238,511Thaxter Apr. 15, 1941 2,706,387 Swanson Apr. 19, 1955

